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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 22 |
| 4 | 195 |
| 5 | 1938 |
| 6 | 20622 |
| 7 | 229836 |
| 8 | 2648547 |
| 9 | 31301050 |
| 10 | 377301210 |
| 11 | 4620769140 |
| 12 | 57333249870 |
| 13 | 719179311732 |
| 14 | 9105192433980 |
| 15 | 116197502184984 |
| 16 | 1493159297251491 |
| 17 | 19303993468386378 |
| 18 | 250907887026047010 |
| 19 | 3276818401723155300 |
| 20 | 42977976005402922330 |
| 21 | 565863442299520006620 |
[1,3,22,195,1938,20622,229836,2648547,31301050, 377301210,4620769140,57333249870,719179311732, 9105192433980,116197502184984,1493159297251491, 19303993468386378,250907887026047010, 3276818401723155300,42977976005402922330, 565863442299520006620] |